The Failure of Facial Recognition Tools – Lessons for Healthcare

The headlines yesterday reported that police facial recognition tools were ‘staggeringly inaccurate’. The idea is that cameras scan faces in a crowd – for instance, at a football match – and match faces to those on a police database, thereby helping the police to identify known offenders. On the face of it, the numbers do sound extraordinary, since over 91% of those identified as being a known suspect turn out to be innocent members of the public – but should we be ‘staggered’ to find out that the technology performs so badly? The maths suggests the opposite – it was almost certain that the numbers would be this poor.

The maths is not difficult. Let’s assume that the cameras are going to be used at a football match attended by 50 000 fans, and that every fan goes through the recognition software. Let’s also assume, for a moment, that this is a particularly crime-ridden football match and 10% of those attending are on the police database – so there would be 5 000 offenders in the crowd.

I’ve not been able to find out how good the technology is on a case-by-case basis, but let’s assume it is accurate 90% of the time – because that sounds like quite a good test and makes my maths easier in the process! That means that it will successfully identify 9 out of 10 of the criminals, and also 9 out of 10 of the innocent bystanders.

So for 5 000 criminals it will identify 9 out of 10, which is 4 500 and miss 500 – not too bad.

For 45 000 innocent bystanders it will correctly identify 9 out of 10, which is 40 500, but it will mistakenly identify 4 500 as potential criminals.

Put these together and we have 4 500 criminals and 4 500 innocent bystanders that the police think are criminals – a 50% success rate, or a 50% failure rate, depending on which way you look at it.

Now look what happens if we have a more realistic number of criminals in the crowd – surely even the worst football clubs don’t have 5 000 criminals at every match! What if only 1 in 1000 fans are criminals? Maybe I’m naive, but the idea that 50 known criminals are in every football match still seems like quite a high number to me. We can do the same maths.

Out of the 50 criminals, the police will identify 45 and miss 5.

Out of the 49 550 innocent bystanders, the police will correctly identify 90%, which is 44 595, but will incorrectly identify 10%, which would be 4 955.

4955 is a similar number to the first example, but now a far higher portion of the total, since there are only 45 identified criminals – a 99% failure rate. All of a sudden, the 92% failure rate by the police seems more understandable!

The big problem is that when you are looking for something rare, the chance of a false positive result (the innocent bystander being thought to be a criminal in this case) starts to massively outweigh the number of true positives unless your test is fabulously good. In fact, if only 1% of the crowd is a criminal, facial recognition software would have to get it right not 90% of the time, but over 99.9% of the time just to get a success rate of 50%. If the police have any mathematicians on board, they should know this.

So what does this mean for health? In health we often do tests where we are trying to find something important when the chances are much more likely that nothing serious is going on. The obvious example is screening – when we test patients who have no symptoms in order to make sure that if there is a problem then we find it early enough to deal with it – such as mammograms in the breast screening programme, PSA testing for prostate cancer, or a treadmill test to look for heart disease. Other examples are when doctors and nurses arrange tests routinely – such as an ECG and a Chest x-ray for most people who attend A&E with any hint of chest pain – or ‘just in case’ tests to make sure we are not missing anything. These tests may all be of value, of course, but the lesson we must learn is that when the chance of finding a true positive result is low, the problem of false positives can become a huge problem.

What really matters then is to consider the possible consequences of a false positive – it might be something fairly minor, like having to be recalled for a repeat blood test, or it could involve unnecessary procedures like a biopsy, or an invasive angiogram to check someone’s heart is ok. Then there is the anxiety that can be caused, and the waste of health resources spent separating false positives from true positives.

These are difficult, complex issues, but if we can learn something from the problem the police are facing, we might get better, as both healthcare professionals and patients,  at asking these sorts of questions before we arrange any test:

• Do we need to do this test?
• How likely is the condition that we are testing for?
• How likely is it that the test will result in a false positive?
• What are the consequences of a false positive?
• What might happen if I don’t do the test?

Challenging stuff!

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DNACPR – have we got the language right?

Decisions around cardiopulmonary resuscitation can be fraught with difficulty at the best of times; you are talking about what to do when someone’s heart stops, which is never an easy subject. I have been thinking for a while that the language doctors use is an added barrier to a good understanding of the issues, and I have had an Opinion piece published in the ~British Medical Journal which is free to read and can be found here. I hope it might be of interest.

You have to subscribe to the journal to be able to leave a comment, but do feel free to leave a comment here if you have anything to add to this important discussion.

The Real Driver Behind the Pfizer Fines

The record £89.4m fines imposed by the Competition and Marketing Authority on Pfizer and Flynn Pharma just before Christmas were a real good news story for the NHS. While I wrote about the story, my own efforts 4 years ago drew a blank in terms of actually making things happen, and it was Dr Stephen Pike, a GP in Shoreham-by-Sea, West Sussex, who has been the real driver behind the CMA investigation that has ultimately led to this landmark judgment. Dr Pike made a formal complaint, on behalf of Coastal West Sussex CCG to the Office of Fair Trading (the forerunner of the CMA) at the end of October 2012, and contacted me in February 2013 to let me know the good news that a formal investigation was to take place. In the 4 years that have followed, Dr Pike has been assisting the CMA in their investigation, and so has needed to keep his own name out of the news until the final verdict had been reached. Now the CMA has reached its verdict, the pivotal role Dr Pike has played in this investigation can be acknowledged, and the credit given where it is due.

That a pharmaceutical giant has been called to account for its actions in this way is a fantastic achievement. What is more, Stephen plans to seek a compensatory payment in addition to the imposed fine, from both Pfizer and Flynn Pharma for the losses incurred by CCGs as a result of the excessive pricing of phenytoin capsules for the past four years, to be re-invested by CCGs back into patient care. This is where the real impact of this judgement could be felt – since the compensation could be significantly more than the fines, and will have to be paid back to the CCGs and not go to the Exchequer.

7971:1 – What will you trust when it comes to the safety of HRT?

You get used to outrageous medical claims in the press, but The Telegraph has truly surpassed itself today with its front page headline declaring that ‘HRT ‘is safe’ for postmenopausal women after all‘.

The article states that new research ‘has found no evidence that HRT is linked to any life-threatening condition’, and makes much of the fact that the new study followed women for a decade. There is a quote from Dr Lila Nachtigall, one of the study authors and a Professor of Obstetrics and Gynaecology at New York University who claims that: ‘the risks of HRT have definitely been overstated. The benefits outweigh the risk.’

Prof John Studd from London is even more forthright, saying: ‘Most GPs are afraid of HRT – they will have learnt as medical students that it is linked to health risks. But those studies that were replicated in the textbooks were worthless. They collected the data all wrong.’

These are bold statements, and so you would expect them to be based on a significant piece of research. The main study that Prof Studd so comprehensively dismisses is the British Million Women study – over 1 million women were studied specifically to look at the risk of breast cancer with HRT and it found a small, but significant, increased risk. To overturn the findings of such a significant piece of research would require something big.

So what is this new research? Well the article, as is so often the case, fails to tell you – but if you are still reading as far as the 11th paragraph you may start to have your doubts: the study followed 80 women. 80! Not 800 000, or even 80 000, but 80! To be fair, when you look at the study itself it’s actually 136 – 80 women on HRT and 56 without. So with 1 084 110 women in the million women study and 136 in this new, apparently game-changing research – that’s 7971:1.

What’s more, when you look at the new study in detail (and here I’m grateful to Adam Jacobs on twitter who managed to locate it) the study was not designed to look at the safety of HRT – the intention of the research was to answer a question about the effects of HRT on body fat composition, and any findings on the safety of HRT were only a secondary consideration. What is more, it is described as a retrospective cohort study – that means it looked backwards at the history of these 80 women, so if a woman had got breast cancer related to HRT she might not have been alive to take part in the study in the first place.

Even if the study had been designed to prove there was no link between breast cancer and HRT, the Million Women study suggests an increase of only 5 extra breast cancers in 1000 women taking HRT for 10 years – so 80 women would only have 0.4 extra breast cancers between them – meaning the study is far too weak to draw any conclusions at all. Oh – and the study was sponsored by Pfizer, who might just have a commercial interest in lots more women going on HRT.

The Telegraph was not the only newspaper to pick up the story, but it was by far the worst reporting among the broadsheets – The Guardian, for instance, picked up the small number of women in the study and tried to bring a sense of balance to its piece – just so long as you read past the headline and the first two paragraphs.

In closing, I would like to say one or two things to Prof John Studd of Wimpole Street. The first is that if you are going to have an official website it would be best, for reasons of probity, if you could include an easy to find declaration of interests; maybe I am being dense, but I failed to find yours. Secondly, GPs are not afraid to prescribe HRT – and we have learnt one or two things since medical school – but we do like to prescribe it after having a discussion with the woman concerned about the balance of benefits versus risk, as we like to base this on reliable evidence.

And for a woman considering HRT wondering what all this means? HRT remains the best way to control symptoms of the menopause, which can be very distressing. There is an increased risk of some cancers, but it really is quite small and many woman feel it is well worth taking that risk in order to feel well; have a chat with your GP about it.

 

Art Therapy

I decided to have a go at a technique called ‘Aux Trois Crayons’ that uses only 3 colours – black, white and red. The girl is not someone I know, but a photo I thought would be fun to draw.

Recently, I’ve been trying to practise what I preach. I frequently find myself asking patients questions like this:

How do you destress?

What about some ‘you time’?

Or: What could you do that you know usually makes you feel good?

What I love about these questions is that I can never predict the answer – the things that make us feel good, that so absorb us they have the power to take us away from our present situation and help us forget our stresses for a while, are very personal. For one person it will be exercise; going on a run, working out in the gym or swimming 50 lengths. For another it might be music – listening to it or playing – while a third will find it helps to occupy their mind with a crossword or a sudoku.

The answer I would give is ‘Art’ (oh, and gardening, but that’s for another post!)

I never did art at school, but have loved it ever since – even more so since I learnt the importance of enjoying the process more and worrying about the end product less. When I paint or draw I have to concentrate so hard on what I am doing that there is no space left in my head to worry about anything else; any stresses that might be lurking there are pushed out by thoughts about line, tone and colour; time takes on a different quality as minutes turn into hours with unexpected swiftness and I have to set an alarm if I have something important to remember.

Her hair was always going to be the biggest challenge so it was good to be able to make some headway with it.

Most of all, I know that it does me good – and that I don’t do it often enough.

In the whole of 2014 I only managed the time to paint one picture and I am trying to rectify that this year – which is partly why the blog posts are coming less frequently. Making time for things that do us good means deciding what is important, and takes a bit of planning; the things that help often get pushed out by all the other, more urgent – but arguably less important – stresses in our lives.

Finding a regular time for art this year has really made the difference, and has come in the form of a monthly art space at my church. It’s not a class as such, since there’s no teacher, but we have a quiet room to use, regular tea and coffee and a mix of fruit and cake to keep us going; there’s no need for any talent, just enthusiasm for doing something creative and a willingness to spend a Saturday morning with others doing the same.

We’ve only met twice so far, but it’s got me drawing again at other times in the week too and now I’ve finished the picture I’ve been working on, I thought I’d share it here. On the whole I’m quite pleased with it, and it’s been great to try out a completely new technique – I’ve done a few charcoal portraits before, but not tried the 3 pencil technique before, and it’s emboldened me to have a go at a full colour pastel portrait next time. More than anything, it is a sign to me of 12 hours well spent, and it has done me a great deal of good.

Now she has hair on both sides of her face I’m trying to work on the balance of light and dark as the light is all coming from over her left shoulder – the hair over her right eye seems too light to me.

There’s a bit in the Bible that I’m reminded of here – something that I’m sure we could all relate to, whatever our position when it comes to matters of faith, and it is this:

Finally brothers and sisters, whatever is true, whatever is noble, whatever is right, whatever is pure, whatever is lovely, whatever is admirable – if anything is excellent or praiseworthy – think about such things. (Phil 4 v 8)

I’d encourage everyone to think about things that do them good, and more than that, to make time to do them. It might not be Art Therapy  – it could be Park-Run Therapy, Family-Weekend-Walk Therapy, Knitting Therapy or Origami Therapy – whatever it is, try to find time to fit it in if you can.

The finished picture – her hair looks more balanced now, with more warmth added to the hair on the right side.

95% Less Harmful – the Story of a Statistic

When Public Health England (PHE) published their recent report on e cigarettes, the statistic to hit the headlines was the claim that the electronic variety were ‘95% less harmful’ than standard cigarettes. It’s a figure that will have entered the collective consciousness of journalists and vaping enthusiasts, and I can guarantee that we will hear it quoted again and again in coming months and years.

The question is: where has it come from, and what does it mean?

The first question is easy to answer: the 95% figure does not come from PHE. Their report simply quotes the estimates made by another group of experts published by Nutt et al in European Addiction Research. Simply put, PHE have said: ‘other experts have guessed that e cigarettes are 95% less harmful than standard cigarettes, and that seems about right to us.’

The over reliance on the findings of another group of experts has received some very public criticism – most notably in an editorial in The Lancet when it emerged that the findings of this group had been funded by an organisation with links to industry, and that three of its authors had significant financial conflicts of interest. These are valid points, although they may have been made better if The Lancet had included the author’s name and declaration of interests alongside the editorial.

The second question is harder to answer, and here is my main concern with how the 95% figure has been presented. What does ‘95% less harmful’ actually mean?

If I were a smoker, wondering whether to switch to vaping, I would primarily be interested in one thing: how harmful are they to me. In other words – am I less likely to die or get ill if I switch to e cigarettes?

Well, the PHE report would seem to answer this question – in the forward to the full report the authors state that e cigarettes are ‘95% less harmful to your health than smoking.’ The trouble is that the report where they obtained the 95% figure looked at far more than just the effects of smoking on the health of an individual.

The piece of work by Nutt and colleagues involved a group of experts being asked to estimate the harm of a range of nicotine products against 12 different criteria – these included the risk to individual health, but also other societal harms such as economic impact, international damage and links with crime. The 95% figure was only achieved after all 12 factors were weighted for importance and then each nicotine containing product was given a composite score.

Now the propensity for a commercial product to be linked with criminal activity may be very important to PHE, but it wouldn’t influence my individual health choice, nor the advice I would want to give to patients.

Moreover, the work by Nutt and colleagues includes this statement: ‘Perhaps not surprisingly, given their massively greater use as compared with other products, cigarettes were ranked the most harmful.’ So the research was greatly influenced by the extent to which products are used. On this basis you could conclude that drinking wine is more harmful than drinking methylated spirits – on a population basis this is true, but it would be a poor basis for individual advice. 

In response to the criticism in The Lancet, PHE produced a subsequent statement in order to try to achieve some clarity over the 95% figure – only to muddy the waters further by claiming that the figure was linked to the fact that there are 95% fewer harmful chemicals in e cigarettes than standard cigarettes. This may well be true – but it is not the reason why they gave the 95% figure in the first place. It also assumes a linear relationship between the amount of chemical and the degree of harm – 5% of the chemical might only cause 1% of the harm, or it could be 50%.

One of the main problems I have with the 95% statistic, therefore, is one of principle – I just don’t like being duped by the misuse of statistics.

My second issue, however, is more pragmatic: the statistic does not help us with some of the key questions we need to answer.

That e cigarettes are safer than standard cigarettes is not much in doubt – mostly on the basis that smoking is so bad for health that it isn’t hard to beat. There is clearly much to be gained by smokers switching to the electronic variety. The next question concerns what smokers should do next.

Much is said about e cigarettes being an aid to quitting, but what is unique about them is that people often stay with them for the longterm, in a way that they would never consider with something like a nicotine patch. This may be their greatest strength – people may be able to quit who could never do so before – but it is also a new phenomenon as longterm nicotine substitution becomes the norm.

Are e cigarettes so safe that once smokers move over to them they can consider the job done? Many vapers talk about it in these terms. For the short term, it seems they are safe. They have been in common use for 5-8 years and there have been no major concerns so far (although acute poisoning is a new problem with liquid nicotine) – but then the same is true for cigarettes where it is use over decades that is the problem. For me, the 95% figure is too questionable to be able to help here.

There are more dilemmas I face as a doctor since I need to know how to interpret the health risks of someone who uses an electronic cigarette. When it comes to cardiovascular risk, should I consider them a smoker, a non-smoker, or something in between? If they have a persistent cough, do I suggest a chest x-ray early on the grounds that they are at increased risk, or can we watch and wait for a while?

We are a long way from being able to answer questions like this, and I would have preferred a little more honesty from PHE about what we don’t yet know, a little less reliance on the opinions of experts, and only to be presented with a figure like 95% if it is based on hard, objective evidence.

I haven’t Been Paid to Write This

There were two items in the news last week that created an interesting juxtaposition on the issue of transparency.

The first concerned the new guidelines for Vloggers – those entrepreneurial YouTubers who have managed to create a following by recording short video clips of their lives, hoping to earn a few pounds along the way.

Some, it seems, have been earning extra money by being paid to recommend products to their viewers – Oreo biscuits being the most high profile example – and such is their influence that new rules have been established to make sure the unsuspecting public know money has changed hands. In short, they can recommend anything they like, but must make a clear declaration if they’ve been paid to do so.

The BBC news cheerfully put together item where three young female Vloggers dutifully explained the new rules, gaining some useful exposure for their own YouTube channel along the way.

You can hardly object to the rules; transparency is important and the consuming public should not be misled.  These young women hardly seemed to be a major threat to society, though, and you couldn’t help thinking that the establishment had come down hard on some enterprising young people who had found a way to start saving for a mortgage.

The second item concerned e cigarettes. Public Health England had produced a report stating that e cigarettes are ‘95% less harmful’ than standard cigarettes and suggesting that they should be prescribed on the NHS in the future.

The report is not a new study, but the opinion of a group of experts who have looked at all the evidence that is out there and given us the benefit of their combined wisdom.

Now, when a Vlogger declares one brand of biscuit to be superior to another, we have a right to know whether or not they have any financial incentive to say so; as Shahriar Coupal, director of the Committee of Advertising Practice says: ‘it’s simply not fair if we’re being advertised to and are not made aware of that fact.’

So what if a scientific expert declares one type of cigarette to be safer than another? Do we not have the same right to know whether the expert has had any financial dealings with the makers of cigarettes? Good medical practice would certainly say so, but the practical reality is often very different.

I have looked at the report in detail. The names of the authors are clear, but nowhere in its 111 pages can I find any declaration of interests; I have no way of knowing whether or not these authors have been paid by the makers of e cigarettes.

Which is more important? The type of biscuit someone may buy after watching a video on YouTube, or the health advice given to the nation by Public Health England on something as topical as e cigarettes?

I’m not stating that the authors do have any conflict of interests – they may well be entirely free from such ties – but the issue is that I cannot tell. If they have no such links, then tell me – I will be far more willing to trust the opinion of these experts if that is the case. If, on the other hand, they have received money from industry, then I have both a right and a need to know – for the sake of my patients and the advice I may pass on to them.

The authors may have made declarations of interests elsewhere, but this is no good to me since I don’t know where to look, and anyway, why should I be required to hunt for them? The Vloggers have to make a declaration on the page where they advertise the product, it should be no different for Public Health England.

Why are these declarations so often absent in reports like this? Is it thoughtlessness, laziness, or something more sinister? I don’t know, but it should be different. We need a culture change until it becomes unthinkable to publish such a report without them. We need a media that will focus the story on the lack of such a declaration rather than on the report itself – which is, after all, meaningless without it.

So what do I think of the report itself? Sadly, until I know if I can trust its authors I just don’t think I can make a judgement.

Addendum

As you will be able to see from the comments below, Public Health England have amended the report to include full DOI on pages 90 and 91 which is great news!

A Library in the Surgery

Every once in a while, someone who knows you well will recommend a book for you to read – not just the last novel they happened to race through on holiday, but something they have carefully put aside for you, knowing how much you will enjoy it. A personal recommendation like this rarely disappoints.

If this is so for fiction, then why not for medical books? If a friend can know you well enough to recommend a good yarn, can your doctor have sufficient insight to guide you towards the right book to help with your health? If you trust your friend enough to follow their lead, will you also take the time to try your doctor’s suggestion?

In my experience, the answer is ‘yes’ more often than not. I’m constantly humbled by how often my patients do get hold of a book I have suggested and take a look inside. I can’t say it is always transformative, but it is usually helpful and frequently makes a big difference to how they approach the challenges they are facing – sometimes they refer back to it even years later.

The Binscombe Library

This is why I was broadly in favour of the Books on Prescription scheme the Government launched a couple of years ago. While I found it mildly irritating that something as simple as getting a book out of the library could depend on some sort of ethereal ‘prescription’ (the concept seems to me to leave the patient in too passive a role), the idea that more books might be available for patients seemed to be a good move.

Two years on, however, I have not recommended a single one of them to my patients.

 

 

The problem is that there are too many steps in the process: First, I have to remember which books are on the list – books I haven’t been able to look through myself since I haven’t visited the library yet to check them out; then I need to recommend the book to my patient, who may not be used to using a public library; finally the patient needs to visit the library, and even then we have to hope the book is available and not already out on loan.

When I visited the Books on Prescription stand at the RCGP conference, therefore, I put these problems to him: ‘wouldn’t it be better if the books were held in a GP practice?’ I suggested. To my surprise, he agreed with me and within a fortnight a full set of all the books had arrived at the practice to form the basis for a new practice library.

Of course, we wanted to add some books of our own choosing and the Binscombe Medical Trust kindly agreed to fund the purchase of more books, the doctors added a few of their own and even the manager of our local Waterstones store made a donation.

The library was launched at the end of July, with 40 books available to browse in the waiting room and free for any of our patients to take out in loan. I’m intrigued to see how it works out.

Will it be a success that we will want to expand and develop over coming months and years, or will the idea of a library in a GP waiting room be so unfamiliar that the books are rarely looked at in favour of the more usual supply of magazines? Or will they be taken out on loan, never to be seen again? They are all clearly marked and we are asking patients to leave a contact number when they borrow one, but library books are notorious for going wandering, so I do worry.

However, it will be great to be able to go and get a copy of a book from the waiting room and show it to someone rather than just talk about it, and good to know that cost won’t be an issue.

I’d be very interested to hear what patients think, and for any suggestions about other titles to bring on board!

Here’s what’s in the library at the moment.

A Covenant and not a Contract

It has been an intense winter and in the three-way tussle between doing the day job, staying healthy and blogging it was always the writing that would have to give. It’s good to be back, though, and with renewed energy – although how long that lasts may well depend on which Government is elected on May 7^th, and what they decide to throw at General Practice over the next five years.

It’s good to start afresh with a positive blog – one, oddly enough, inspired by the Care Quality Commission (CQC). I’m not the greatest fan of inspections, nor have I been impressed by the approach taken by the CQC as it has moved into doctors’ surgeries, but there are times when doing something you don’t want to do bears unexpected fruit.

One of the requirements of the CQC is that GP practices should have a ‘Vision and Values Statement’ that all staff should be familiar with. Knowing that we could be quizzed on such a statement at any time during an inspection, and that it would be hard to give the right answers if we didn’t actually have one, we set about to rectify the situation.

I confess to having an attitude more becoming of a teenager told to tidy their bedroom; just as an adolescent is convinced that they know where everything is in their own private world and so what is the point of tidying just to please Mum and Dad, so I knew that we understood our values and wondered what good could possibly come of writing them down just to tick a box.

It all felt very corporate. We looked for examples from others so that we would not have to reinvent the wheel, but they left us feeling flat and uninspired – they were other people’s values and not ours so they just didn’t resonate. It turns out, that when it comes to what really matters to you it’s best to invent your own wheel after all.

Then I remembered a line I’d heard about General Practice that had excited me and it was this: that the relationship between a GP and their patient should be a Covenant and not a Contract.

From that beginning, it suddenly became easy – and I am converted: writing down your values is worthwhile after all; it really did help to be able to look at them together as a practice and say ‘yes, this is what gets us up in the morning’; it’s helpful to remember them on a bad day when you’re tired and you’ve lost sight of what you believe in; it’s good to know that they are there as a yardstick for us to measure ourselves by – and one that we have put there on our own account rather than something that has been imposed upon us.

It feels scary to do so, but we would like our patients to know our values, and would like to know what they think of them. They are ideals – some would say idealistic – and we know we won’t always live up to them. What will happen when we fail? How will we feel if a patient throws them back in our face and tells us how badly we have let them down and how hypocritical we must be? It’s a risk we will have to take, but it feels a risk worth taking. More likely is that our patients will help us to shape these values further and improve them.

So, we have published them on our website, and we’d be interested in your thoughts.

Should Policy Makers Tell GPs How Often to Diagnose?

I’m sure NHS England were surprised by the response to their plans to pay GPs £55 every time they diagnosed dementia. What started as a seemingly simple idea to help the Government hit their diagnosis target before the election caused such a furore that Simon Stevens declared the end of the policy before it had really begun, making it clear that it would end at the end of March.

What was striking about the reaction was not the objection among GPs – policy makers are used to that and well accustomed to ignoring it – but the strength of feeling among the public. I’m sure this is what made the difference – no politician wants to lose in the arena of public opinion. It’s not hard to see how this happened. There was something innately wrong about paying GPs to diagnose; no in-depth analysis was needed, no exploration of the evidence – it was just so clearly a bad idea and both doctors and patients were alarmed at want it meant for the doctor-patient relationship.

What continues to concern me, though, is that policy-makers still think they know best when it comes to how many patients GPs should diagnose with a variety of conditions – from heart disease to asthma, diabetes and even depression – and have an even more powerful mechanism for enforcing this, which is to put pressure on practices with low diagnosis rates through naming and shaming, and the threat of inspection. A practice may have the moral courage to resist a financial bribe, but what about if the reputation of your practice is at stake?

I have written in the British Medical Journal about this, published this week, and this is a toll-free link if you are interested. What is crucial is that at the moment of diagnosis there should be nothing in the mind of the GP other than what is best for the patient – it is fundamental to the doctor-patient relationship and something well worth shouting about.